C# 如何在asp.net core中startup.cs文件的configure方法中更改作用域服务的属性值
我将在startup.cs文件中更改或向作用域服务插入一些值 这是我的密码 我正在向MyService.SomeData属性插入一个值。但是,在查看页面中,打印空值 为什么呢 Startup.csC# 如何在asp.net core中startup.cs文件的configure方法中更改作用域服务的属性值,c#,asp.net-core,.net-core,C#,Asp.net Core,.net Core,我将在startup.cs文件中更改或向作用域服务插入一些值 这是我的密码 我正在向MyService.SomeData属性插入一个值。但是,在查看页面中,打印空值 为什么呢 Startup.cs namespace MyProject { public class Startup { . . . public void ConfigureServices(IServiceCollection services)
namespace MyProject
{
public class Startup
{
.
.
.
public void ConfigureServices(IServiceCollection services)
{
.
.
.
services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
services.AddScoped<MyService>();
}
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
var scope = app.ApplicationServices.CreateScope();
var MyService = scope.ServiceProvider.GetService<MyService>();
app.Use(async (context, next) =>
{
if (context.Request.Query.ContainKey("conditionKey") && context.Request.Query["conditonKey"] == "something")
{
MyService.SomeData = "foo";
}
});
}
}
}
namespace MyProject.Service
{
public class MyService
{
public string SomeData { get; set; } = "";
{
}
MyView.cshtml
@inject MyProject.Service.MyService MyService
<!DOCTYPE html>
<html lang="en">
<head>
</head>
<body>
<div>@MyService.SomeData</div>
</body>
@injectmyproject.Service.MyService MyService
@MyService.SomeData
ASP.NET核心管道为每个http请求创建作用域,因此您需要在操作方法中设置此属性
public class HomeController : Controller
{
private readonly MyService myService;
public HomeController(MyService myService)
{
this.myService = myService;
}
public IActionResult Index()
{
myService.MyData = "MyData";
return View();
}
}
或者将您的服务注册为singleton
public void ConfigureServices(IServiceCollection services)
{
services.AddSingleton<MyService>();
}
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
var scope = app.ApplicationServices.CreateScope();
var MyService = scope.ServiceProvider.GetService<MyService>();
MyService.MyData = "SomeData";
}
多亏了@YegorAndrosov,我解决了这个问题。 在app.Use()中间件中创建请求范围的服务。并且,通过context.RequestServices.GetService()创建它
名称空间MyProject
{
公营创业
{
.
.
.
public void配置服务(IServiceCollection服务)
{
.
.
.
services.AddSingleton();
services.addScope();
}
.
.
.
public void配置(IApplicationBuilder应用程序、IWebHostEnvironment环境、ILogger记录器)
{
.
.
.
应用程序使用(异步(上下文,下一步)=>
{
var RequestData=context.RequestServices.GetService();
var HompageSetting=context.RequestServices.GetService();
if(context.Request.Query.ContainKey(“conditionKey”)&&context.Request.Query[“conditonKey”]=“something”)
{
MyService.SomeData=“foo”;
}
等待下一个();
});
}
}
}
它的作用域是有限的,每个作用域都会得到一个新实例,所以这不起作用。使用工厂方法注册服务,或者将配置类型作为另一个服务依赖项注入。感谢您的回答Jeremy.yap,我将使用新实例。所以,我修改了我的代码。数据已插入app.Use()lambda。但它是一样的。@Jang HoBae如果您在使用之外创建MyService,它应该是inside@Jang-HoBae我更新了我的答案以使用app.use()
,感谢你的回答Yegor~。是的,我将使用新实例。所以,我修改了我的代码。数据已插入app.Use()lambda。但这是一样的。你需要接受最有用的答案,或者如果没有人解决你的问题,就发表你自己的答案。请不要张贴答案的副本。
public void ConfigureServices(IServiceCollection services)
{
services.AddControllersWithViews(x => x.Filters.Add(typeof(MyServiceFilter)));
services.AddScoped<MyService>();
}
public class MyServiceFilter : IActionFilter
{
private readonly MyService myService;
public MyServiceFilter(MyService myService)
{
this.myService = myService;
}
public void OnActionExecuted(ActionExecutedContext context)
{
}
public void OnActionExecuting(ActionExecutingContext context)
{
myService.MyData = "MyData";
}
}
app.Use(async (context, next) =>
{
if (context.Request.Query.ContainsKey("conditionKey") && context.Request.Query["conditionKey"] == "something")
{
var myService = context.RequestServices.GetService<MyService>();
myService.MyData = "foo";
}
await next();
});
namespace MyProject
{
public class Startup
{
.
.
.
public void ConfigureServices(IServiceCollection services)
{
.
.
.
services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
services.AddScoped<MyService>();
}
.
.
.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILogger<Startup> logger)
{
.
.
.
app.Use(async (context, next) =>
{
var RequestData = context.RequestServices.GetService<RequestData>();
var HompageSetting = context.RequestServices.GetService<HomepageSetting>();
if (context.Request.Query.ContainKey("conditionKey") && context.Request.Query["conditonKey"] == "something")
{
MyService.SomeData = "foo";
}
await next();
});
}
}
}